Sign holder



FIG. 1 is a front perspective view of a sign holder showing my new design;

FIG. 2 is an enlarged left side elevational view thereof, with the opposite side being a mirror image;

FIG. 3 is a top plan view thereof, with the center broken away for ease of illustration;

FIG. 4 is a front elevational view thereof, with the rear being a mirror image;

FIG. 5 is a bottom plan view thereof. 

The ornamental design for a sign holder, as shown and described. 